(a) Field of the Invention
The present invention relates to a construction of the keyboard switch used as an input unit for personal computers, word processors and the like.
(b) Prior Art
In the case of the keyboard switch comprising a plurality of switches arranged on a sheet of base plate, switches to each of which a key top of common size (1.times.1) is attached and those to each of which a large key top (1.times.2 or 1.times.3) used as the function key or the like is attached are arranged on the base plate and various kinds of circuit parts except these switches are mounted on the base plate as well. Therefore, the base plate is needed to have a space for the switches and another space for the circuit parts. The construction of the conventional keyboard switch will be described with reference to FIG. 4. Numeral 21 represents an attachment plate made of iron, and switches 22, 23 and 24 to which key tops of common size are attached and a switch 25 to which a large key top is attached are arranged on the attachment plate 21. A part of the attachment plate 21 is cut away to form a space in which circuit parts are mounted on a base plate 26. Numeral 27 denotes one of high circuit parts which corresponds to the choke coil, for example. Numeral 28 denotes one of low circuit parts which corresponds to the fixed resistor, for example. The low circuit parts can be arranged between the attachment plate 21 and the base plate 26, but the high circuit parts cannot be mounted on the base plate 26 without cutting away a part of the attachment plate 21, as shown in FIG. 4. The base plate 26 is thus needed to have the space for the circuit parts in addition to the other space for the switches.